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1.
Adv Sci (Weinh) ; 9(36): e2205575, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36310102

ABSTRACT

Currently, the construction of amorphous/crystalline (A/C) heterophase has become an advanced strategy to modulate electronic and/or ionic behaviors and promote structural stability due to their concerted advantages. However, their different kinetics limit the synergistic effect. Further, their interaction functions and underlying mechanisms remain unclear. Here, a unique engineered defect-rich V2 O3 heterophase structure (donated as A/C-V2 O3- x @C-HMCS) composed of mesoporous oxygen-deficient amorphous - hollow core (A-V2 O3- x /HMC) and lattice-distorted crystalline shell (C-V2 O3 /S) encapsulated by carbon is rationally designed via a facile approach. Comprehensive density functional theory (DFT) calculations disclose that the lattice distortion enlarges the porous channels for Na+ diffusion in the crystalline phase, thereby optimizing its kinetics to be compatible with the oxygen-vacancy-rich amorphous phase. This significantly reduces the high contrast of the kinetic properties between the crystalline and amorphous phases in A/C-V2 O3- x @C-HMCS and induces the formation of highly dense A/C interfaces with a strong synergistic effect. As a result, the dense heterointerface effectively optimizes the Na+ adsorption energy and lowers the diffusion barrier, thus accelerating the overall kinetics of A/C-V2 O3- x @C-HMCS. In contrast, the perfect heterophase (defects-free) A/C-V2 O3 @C-HCS demonstrates sparse A/C interfacial sites with limited synergistic effect and sluggish kinetics. As expected, the A/C-V2 O3- x @C-HMCS achieves a high rate and ultrastable performance (192 mAh g-1 over 6000 cycles at 10 A g-1 ) when employed for the first time as a cathode for sodium-ion batteries (SIBs). This work provides general guidance for realizing dense heterophase cathode design for high-performance SIBs and beyond.

2.
J Phys Chem Lett ; 12(30): 7076-7084, 2021 Aug 05.
Article in English | MEDLINE | ID: mdl-34292751

ABSTRACT

Because they are safer and less costly than state-of-the-art Li-ion batteries, aqueous zinc-ion batteries (AZIBs) have been attracting more attention in stationary energy storage and industrial energy storage. However, the electrochemical reaction of H+ in all of the cathode materials of AZIBs has been puzzling until now. Herein, highly oriented VO2 monocrystals grown on a Ti current collector (VO2-Ti) were rationally designed as the research model, and such a well-aligned VO2 cathode also displayed excellent zinc-ion storage capability (e.g., a reversible capacity of 148.4 mAh/g at a current density of 2 A/g). To visualize the H+ reaction process, we used time-of-flight secondary-ion mass spectrometry. With the benefit of such a binder-free and conductor-free electrode design, a clear and intuitive reaction of H+ in a VO2 cathode is obtained, which is quite significant for unraveling the accurate reaction mechanism of VO2 in AZIBs.

3.
ACS Appl Mater Interfaces ; 13(1): 816-826, 2021 Jan 13.
Article in English | MEDLINE | ID: mdl-33395248

ABSTRACT

Sodium vanadate NaV6O15 (NVO) is one of the most promising cathode materials for sodium-ion batteries because of its low cost and high theoretical capacity. Nevertheless, NVO suffers from fast capacity fading and poor rate capability. Herein, a novel free-standing NVO/multiwalled carbon nanotube (MWCNT) composite film cathode was synthesized and designed by a simple hydrothermal method followed by a dispersion technique with high safety and low cost. The kinetics analysis based on cyclic voltammetry measurements reveals that the intimate integration of the MWCNT 3D porous conductive network with the 3D pillaring tunnel structure of NVO nanorods enhances the Na+ intercalation pseudocapacitive behavior, thus leading to exceptional rate capability and long lifespan. Furthermore, the NVO/MWCNT composite exhibits excellent structural stability during the charge/discharge process. With these benefits, the composite delivers a high discharge capacity of 217.2 mA h g-1 at 0.1 A g-1 in a potential region of 1.5-4.0 V. It demonstrates a superior rate capability of 123.7 mA h g-1 at 10 A g-1. More encouragingly, it displays long lifespan; impressively, 96% of the initial capacity is retained at 5 A g-1 for over 500 cycles. Our work presents a promising strategy for developing electrode materials with a high rate capability and a long cycle life.

4.
BMC Neurol ; 20(1): 392, 2020 Oct 27.
Article in English | MEDLINE | ID: mdl-33109106

ABSTRACT

BACKGROUND: Methamphetamine use is an emerging risk factor for intracerebral hemorrhage (ICH). The aim of this study was to investigate the use of urine drug screen (UDS) for identifying methamphetamine-associated ICH. METHODS: This is a retrospective, single-center study of consecutive patients hospitalized with spontaneous ICH from January 2013 to December 2017. Patients were divided into groups based on presence of UDS. The characteristics of patients with and without UDS were compared. Factors associated with getting UDS were explored using multivariable analyses. RESULTS: Five hundred ninety-six patients with ICH were included. UDS was performed in 357 (60%), and positive for methamphetamine in 44 (12.3%). In contrast, only 19 of the 357 patients (5.3%) had a documented history of methamphetamine use. Multivariable analysis demonstrated that patients screened with UDS were more likely to be younger than 45 (OR, 2.24; 95% CI, 0.26-0.78; p = 0.004), male (OR, 1.65; 95% CI, 0.44-0.84; p = 0.003), smokers (OR, 1.74; 95% CI, 1.09-2.77; p <  0.001), with history of methamphetamine use (OR, 10.48; 95% CI, 2.48-44.34; p <  0.001), without diabetes (OR 1.47; 95% CI, 0.471-0.975; p = 0.036), not on anticoagulant (OR, 2.20; 95% CI, 0.26-0.78; p = 0.004), with National Institutes of Health Stroke Scale (NIHSS) > 4 (OR, 1.92; 95%CI, 1.34-2.75; p <  0.001), or require external ventricular drain (EVD) (OR, 1.63; 95%CI, 1.07-2.47; p = 0.021. There was no significant difference in race (p = 0.319). Reported history of methamphetamine use was the strongest predictor of obtaining a UDS (OR,10.48). Five percent of patients without UDS admitted history of use. CONCLUSION: UDS identified 12.3% of ICH patients with methamphetamine use as compared to 5.3% per documented history of drug use. There was no racial bias in ordering UDS. However, it was more often ordered in younger, male, smokers, with history of methamphetamine use, without diabetes or anticoagulant use.


Subject(s)
Cerebral Hemorrhage/chemically induced , Methamphetamine/adverse effects , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Retrospective Studies , Risk Factors
5.
Sci Rep ; 10(1): 6375, 2020 04 14.
Article in English | MEDLINE | ID: mdl-32286468

ABSTRACT

Methamphetamine use has emerged as a risk factor for intracerebral hemorrhage (ICH). We aim to investigate the clinical characteristics and outcomes of methamphetamine-associated ICH (Meth-ICH) versus Non-Meth-ICH. Patients with ICH between January 2011 and December 2017 were studied. Meth-ICH and Non-Meth-ICH were defined by history of abuse and urine drug screen (UDS). The clinical features of the 2 groups were explored. Among the 677 consecutive patients, 61 (9.0%) were identified as Meth-ICH and 350 as Non-Meth ICH. Meth-ICH was more common in Hispanics (14.6%) and Whites (10.1%) as compared to Asians (1.2%). Patients with Meth-ICH were more often younger (51.2 vs. 62.2 years, p < 0.001), male (77.0% vs. 61.4.0%, p < 0.05), and smokers (44.3% vs. 13.4%, p < 0.001). Non-Meth-ICH was more likely to have history of hypertension (72.61% v. 59%, p < 0.05) or antithrombotic use (10.9% vs. 1.6%, p < 0.05). There was no significant difference in clinical severity, hospital length of stay (LOS), rate of functional independence (29.5% vs. 25.7%, p = 0.534), or mortality (18.0% vs. 24.6%, p = 0.267) between the 2 groups. Methamphetamine use was not an independent predictor of poor outcome. Despite difference in demographics, Meth-ICH is similar to Non-Meth ICH in hospital course and outcome.


Subject(s)
Amphetamine-Related Disorders/physiopathology , Cerebral Hemorrhage/physiopathology , Methamphetamine/toxicity , Adolescent , Adult , Aged , Aged, 80 and over , Amphetamine-Related Disorders/mortality , Cerebral Hemorrhage/mortality , Female , Fibrinolytic Agents/adverse effects , Humans , Hypertension/mortality , Hypertension/physiopathology , Male , Middle Aged , Retrospective Studies , Risk Factors , Young Adult
6.
Sci Rep ; 7: 45926, 2017 04 04.
Article in English | MEDLINE | ID: mdl-28374837

ABSTRACT

Multiple Sclerosis is associated with deficient serum 25 hydroxyvitamin D (25 (OH)D) level and cognitive impairment. The aim of this study is to evaluate cognitive performance in MS patients with deficient 25 (OH)D (<25 ng/ml) compared to patients with sufficient levels (>35 ng/ml), then to evaluate the change in cognitive performance after 3 months of vitamin D3 oral replacement. Eighty-eight MS patients with relapsing remitting and clinically isolated type of MS, older than 18 years treated with interferon beta were enrolled. Cognitive testing was performed at baseline and at 3 months using the Montreal Cognitive Assessment (MoCA), Stroop, Symbol Digit Modalities (SDMT) and Brief Visuospatial Memory Test (BVMT-R). Serum 25 (OH)D was measured at baseline and at the end of the study. Vitamin D3 replacement improved the MS patients' cognitive performance after 3 months on the MoCA and BVMT-Delayed Recall (DR). Sufficient serum 25 (OH)D level predicted better cognitive performance on the BVMT-DR at baseline (ß: 1.74, p: <0.008) and 3 months (ß: 1.93, p: <0.01) after adjusting for all measured confounding variables. Vitamin D3 replacement could improve cognitive performance in MS patients and make a significant difference in the patient's quality of life.


Subject(s)
Cholecalciferol/therapeutic use , Cognition/drug effects , Multiple Sclerosis/drug therapy , Vitamin D Deficiency/drug therapy , Adult , Calcifediol/blood , Cholecalciferol/administration & dosage , Female , Humans , Male , Middle Aged , Multiple Sclerosis/complications , Multiple Sclerosis/psychology , Multivariate Analysis , Neuropsychological Tests , Prospective Studies , Quality of Life , Vitamin D Deficiency/complications , Vitamins/administration & dosage , Vitamins/therapeutic use , Young Adult
7.
PLoS One ; 9(8): e104112, 2014.
Article in English | MEDLINE | ID: mdl-25117518

ABSTRACT

Inducing beta-cell mass expansion in diabetic patients with the aim to restore glucose homeostasis is a promising therapeutic strategy. Although several in vitro studies have been carried out to identify modulators of beta-cell mass expansion, restoring endogenous beta-cell mass in vivo has yet to be achieved. To identify potential stimulators of beta-cell replication in vivo, we established transgenic zebrafish lines that monitor and allow the quantification of cell proliferation by using the fluorescent ubiquitylation-based cell cycle indicator (FUCCI) technology. Using these new reagents, we performed an unbiased chemical screen, and identified 20 small molecules that markedly increased beta-cell proliferation in vivo. Importantly, these structurally distinct molecules, which include clinically-approved drugs, modulate three specific signaling pathways: serotonin, retinoic acid and glucocorticoids, showing the high sensitivity and robustness of our screen. Notably, two drug classes, retinoic acid and glucocorticoids, also promoted beta-cell regeneration after beta-cell ablation. Thus, this study establishes a proof of principle for a high-throughput small molecule-screen for beta-cell proliferation in vivo, and identified compounds that stimulate beta-cell proliferation and regeneration.


Subject(s)
Drug Evaluation, Preclinical , Insulin-Secreting Cells/drug effects , Insulin-Secreting Cells/metabolism , Animals , Animals, Genetically Modified , Cell Cycle/drug effects , Cell Proliferation/drug effects , High-Throughput Screening Assays , Regeneration/drug effects , Small Molecule Libraries , Trazodone/pharmacology , Tretinoin/pharmacology , Ubiquitination/drug effects , Zebrafish
8.
J Neurosci ; 32(21): 7225-31, 2012 May 23.
Article in English | MEDLINE | ID: mdl-22623667

ABSTRACT

Recurrent inhibition, wherein excitatory principal neurons stimulate inhibitory interneurons that feedback on the same principal cells, occurs ubiquitously in the brain. However, the regulation and function of recurrent inhibition are poorly understood in terms of the contributing interneuron subtypes as well as their effect on neural and cognitive outputs. In the Drosophila olfactory system, odorants activate olfactory sensory neurons (OSNs), which stimulate projection neurons (PNs) in the antennal lobe. Both OSNs and PNs activate local inhibitory neurons (LNs) that provide either feedforward or recurrent/feedback inhibition in the lobe. During olfactory habituation, prior exposure to an odorant selectively decreases the animal's subsequent response to the odorant. We show here that habituation occurs in response to feedback from PNs. Output from PNs is necessary for olfactory habituation and, in the absence of odorant, direct PN activation is sufficient to induce the odorant-selective behavioral attenuation characteristic of olfactory habituation. PN-induced habituation occludes further odor-induced habituation and similarly requires GABA(A)Rs and NMDARs in PNs, as well as VGLUT and cAMP signaling in the multiglomerular inhibitory local interneurons (LN1) type of LN. Thus, PN output is monitored by an LN subtype whose resultant plasticity underlies behavioral habituation. We propose that recurrent inhibitory motifs common in neural circuits may similarly underlie habituation to other complex stimuli.


Subject(s)
Arthropod Antennae/physiology , Connexins/physiology , Drosophila Proteins/physiology , Feedback, Sensory/physiology , Nerve Tissue Proteins/physiology , Neural Inhibition/physiology , Olfactory Pathways/physiology , Animals , Animals, Genetically Modified , Connexins/genetics , Cyclic AMP/physiology , Drosophila , Drosophila Proteins/genetics , Dynamins/genetics , Dynamins/physiology , HSP70 Heat-Shock Proteins/genetics , HSP70 Heat-Shock Proteins/physiology , Habituation, Psychophysiologic/physiology , Ion Channels , Nerve Tissue Proteins/genetics , Neurons/physiology , Receptors, GABA-A/physiology , Receptors, N-Methyl-D-Aspartate/physiology , Receptors, Odorant/physiology , Sensory Receptor Cells/physiology , Smell/physiology , TRPA1 Cation Channel , TRPC Cation Channels/genetics , TRPC Cation Channels/physiology , Vesicular Glutamate Transport Proteins/genetics , Vesicular Glutamate Transport Proteins/physiology
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